关节软骨损伤的治疗研究是医学研究的难点，本项目在已有基础上研究原位诱导骨膜祖细胞结合组织工程支架修复软骨损伤的效果及相关机制。通过骨膜下注射TGF-β促进骨膜祖细胞原位增殖，同时研究miRNA-101对骨膜祖细胞成软骨分化的调控机制；最后将原位增殖的骨膜匀浆与含缓释TGF-β微球的壳聚糖水凝胶-脱钙骨双相功能性支架结合，以期提高软骨损伤修复的效果。创新点有：1）原位诱导骨膜祖细胞增殖，通过体内原位标记明确增殖细胞类型；2）研究miRNA-101在骨膜祖细胞向软骨细胞分化的调控机制；3）构建高效的具有缓释生长因子能力的双相功能支架；4）提出保留骨膜祖细胞生长微环境结合组织工程支架修复软骨损伤的新思路。课题将在这一领域首次研究TGF-β促骨膜细胞增殖的类型以及骨膜祖细胞成软骨分化中miRNA-101的调控机制，同时结合双相功能支架修复动物关节软骨损伤的效果，为今后治疗关节软骨损伤提供新的思。

This study employs subperiosteal injection of TGF-β (transforming growth factor- beta) to promote proliferation of PDPCs (periosteal-derived progenitor cells) in cambi-um layer of the periosteum in situ, thus to improve its capacity of chondrogenesis. PDPCs pretreated by TGF-β are combined with solid-supported chitosan hydrogel bi-phasic scaffold, and transplanted into knee joints to induce differentiation of hyaline cartilage to repair cartilage defects. This technique harvests in situ pretreated PDPCs , and there is no need of in vitro culture of stem cells, progenitor cells or chondrocytes. Matrix production and chondrogenic differentiation of PDPCs in the hybrid scaffold are superior to its precursors. Its easy preparation,favourable biophysical properties and chondrogenic capacity indicated that this method could be attractive for cartilage tissue engineering.In conclusion, this technique of cartilage repair is simple to perform and effective in promoting cartilage regeneration. This study will be the first that used TGF-β to improve the proliferation in situ, and transplants the pre-treated PDPCs combined with biphasic scaffold to repair cartilage defects. This method could inspire new approaches for cartilage repair using stem cells, and provide them with scientific basis. This simple and effective approach could be further studied and is promising to be applied in the clinical, which will surely bring enormous benefits.